I put a lot of energy into making sure I added as much B-12 foods as possible to my diet and gag down a B-12 every day. There is nothing I can do re: my mom. She had her thyroid checked. But celiac...isn't diarrhea associated with that? Perhaps her "issue" isn't related to age, but something else. I'll mention it to my dad. What type of test is done?

Coeliac can produce many symptoms , extreme tiredness being one as well , but yes stomach problems if you eat gluten , wheat , barley , rye , oats (you can get gf oats now though ) . It can be diagnosed through a blood test .